The present invention overcomes the problems and disadvantages associated with prior art arrays by providing an array comprising a plurality of biological membrane microspots associated with a surface of a substrate that can be produced, used and stored, not in an aqueous environment, but in an environment exposed to air under ambient or controlled humidities. Preferably, the biological membrane microspots comprise a membrane bound protein. Most preferably, the membrane bound protein is a G-protein coupled receptor, an ion channel or a receptor tyrosine kinase.